Psychological Correlates of Quality of Life in Patients with Burning Mouth Syndrome: The Role of Stress, Anxiety, and Depression

(1) Background: Burning mouth syndrome (BMS) is a chronic pain disorder characterized by a complex clinical picture where oral discomfort and psychological well-being are intertwined. This study examined the psychological correlates of oral health-related quality of life (OHRQoL) in patients with primary BMS, evaluating associations between perceived stress, trait anxiety, depressive symptoms, and OHRQoL. (2) Methods: An observational cross-sectional study included 28 consecutively recruited primary BMS patients. Psychological status and quality of life were evaluated using validated Polish adaptations of self-report questionnaires: OHIP-14, PSS-10, STAI (Form X-2), and BDI. To account for multiple testing, the Benjamini–Hochberg false discovery rate (pFDR) correction was applied. (3) Results: Significant positive correlations were observed between reduced quality of life (higher total OHIP-14 score) and the severity of perceived stress (R = 0.400; p = 0.035; pFDR = 0.055), trait anxiety (R = 0.497; p = 0.007; pFDR = 0.024), and depressive symptoms (R = 0.456; p = 0.015; pFDR = 0.036). These psychological variables correlated strongly with the functional limitation and psychological discomfort subscales (pFDR ≤ 0.050), whereas no statistically significant correlation was found with the OHIP-14 physical pain subscale in this sample (pFDR ≥ 0.500). In an exploratory subgroup comparison, patients with treated thyroid diseases showed lower unadjusted psychological discomfort scores (p = 0.049; rrb = 0.488); however, this difference did not remain statistically significant after FDR correction (pFDR = 0.304). (4) Conclusions: Perceived stress, trait anxiety, and depressive symptoms are significantly associated with poorer OHRQoL in primary BMS patients. These observational findings suggest that integrating psychological screening into dental care may help identify patients experiencing high emotional distress.